A vehicle drive device is well known that includes an engine and a hydraulic power transmission device. For example, this corresponds to a vehicle drive device described in Patent Document 1. Such a vehicle drive device has an engine rotation speed (rotation speed of an input-side rotating element of the hydraulic power transmission device) passively determined depending on a vehicle speed (rotation speed of an output-side rotating element of the hydraulic power transmission device), characteristics of the hydraulic power transmission device, and an engine output. Power transmission efficiency is also passively determined in a mechanical path hydraulically transmitting the engine output through the hydraulic power transmission device.